> Hi, > > Saw something interesting today, hoping someone can confirm. If I run > memcached with these settings: > > memcached -vv -m 1m -I 1m -p 9999 -t 12 -U 0 -D _ -f 1.05 > > There are 182 slab classes. I've set the max memory to 1 meg and my page size > to 1 meg. So in theory memcached should only allocate 1 page. The puzzling > thing is, if I add an object of appropriate size to each of the slab class, > 182 total pages get allocated. meaning > that memcached ends up using ~182 meg of memory. This seemed really odd since > the "max memory" is set at 1meg. > > Now, if I add a billion objects of the SAME size (thus to the same slab > class) my memory remains constant at about 2 megs. This makes sense, since > only 1 page will be allocated to that slab, and no matter how many objects I > put in, other objects will get evicted. > > My conclusion then is, memcached will always assign 1 page to a slab class > and will not do any memory checks on whether this exceeds the -m memory > setting. Anybody confirm? > Much thanks!
Yes that's correct... it was added a long time ago to prevent people from getting OOM errors occasionally on long running instances (where certain slabs are used more rarely). -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
